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An a-peeling proposition - Toronto star

Toronto burns off the biogass produced from the green bin program. Why aren't we using it?

February 9, 2008
Brett Popplewell
Toronto Star

How can a streetcar run on a banana peel?

Simple: Put the peel in a domed compost heap, let its decomposition create biogas, harvest that gas and use it to power a turbine that produces electricity, then channel that electricity into the wires that power the city's streetcars.

It's clean, it's renewable and it's efficient. So why is it not happening?

City residents began separating organic waste with the green bin program in 2002. Since then, the waste has been sent to the Dufferin Organics Processing Facility near Downsview Park, where it decomposes into compost.

But the resulting biogas – a combination of methane gas and carbon dioxide created by the biological breakdown of organic matter – is wasted. Toronto doesn't have the facilities to convert it to electricity, so it is burned.

Franz Hartmann, executive director of the Toronto Environmental Alliance, says the city could be profiting from this waste.

"It's a no-brainer. The goal should be that any city facility that the city sends its green bin stuff to should be taking the methane that's produced from the decomposition and used to produce green power."

Brian Van Opstal, of Toronto's Solid Waste Management Services, says the anaerobic digestion of the 110,000 tonnes of organic material the city collects each year could produce more than 12 million cubic metres of biogas, or 17,000 megawatt-hours of electricity. That would be enough to power 1,700 homes for a year or drive a streetcar 56,667 kilometres. Recognizing this potential profit, the city has a $69 million plan to build two new processing facilities to convert the biogas into $2.5 million worth of electricity a year. That would rise as more compost is used.

Meanwhile, the TTC, which gets its power from Toronto Hydro, aims to purchase at least 25 per cent of its electricity from green sources by 2012. If Toronto follows through with its plans, the TTC wouldn't have to look far for that green energy – the city's streetcars could realistically be powered by banana peels, discarded coffee grounds and other green waste.

A tonne of decomposing banana peels – that's about 66,700 peels at 15 grams per peel – would produce 300 kilowatt-hours of electricity, says Philip Wood, an engineer with the TTC. A streetcar needs about 3.97 kilowatt-hours of electricity to travel 1 kilometre. So theoretically, a tonne of discarded peels could power a streetcar for 76 kilometres. That's three times the length of the city's longest streetcar line, the 501 on Queen St.

The potential for biogas doesn't end in the city's green trash. If a group of Ontario farmers gets its way, Toronto streetcars and houses might soon be powered by cow dung and corn cobs.

With 80 per cent of the province's current electrical energy sources expected to expire within the next 20 years, Ontario has established a $9 million program to assist Ontario farmers who want to produce biogas – seen by some agriculturalists as the future of farming.

However, Graeme Millen of the Agrienergy Producers' Association of Ontario and Benjamin Strehler of Genesys, an Ottawa-based firm that builds anaerobic digesters on Ontario farms, say potential biogas farmers are dissuaded by the queuing system to connect to the grid.

Strehler says the top of the queue is monopolized by wind farmers who, for the most part, have yet to actually build their projects. To join the queue, potential energy producers must pay $5,000 – small change for a large wind energy corporation, but not for a small farmer.

"We could wait for two years in some cases to get permission to get on the grid," says Strehler.

There are only four biogas-producing farms in Ontario, and Millen blames the queue.

George Heinzle of Terryland Farms, near Ottawa, operates one of those farms. He spent $650,000 on a anaerobic digester in 2006. He then waited 10 months to hook up to the grid.

The long-time dairy farmer uses his cows' manure, along with other organic materials, to produce enough electricity to power 100 Ontario homes. (The average Toronto household uses about 27 kilowatt-hours per day.)

"I want to put in a second generator but I can't. All the grid in Ontario is blocked," Heinzle says.

Jim MacDougall, manager of renewable energy with the Ontario Power Authority, says he understands farmers' frustrations. "It doesn't specifically work against biogas farmers, but it's a first-in, first-out queuing system," he says. "The issue really is, the bio digester proponents weren't ready or didn't have their info in order to get (in the queue) when it started."

Still, Millen says Ontario's biogas potential remains clear. He points to Germany – a country with significantly less arable land than Ontario – where biogas will account for 17 per cent of that country's electricity by 2020.

With our lower population, Ontario likely couldn't produce that much, Millen says. But, "if all realistic organic sources in Ontario were used ... then biogas could comfortably satisfy five per cent of Ontario's electricity needs."

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